Camptonlte Dike»^ Etc. — Marsters. 
'.)7 
has its own particular associates. Just what these associates 
are in every case and what the relative position of the plenus 
to the (juaih'angnlarla beds, could not be determined during 
the brief visit paid to the locality by the writer. 
ON CERTAIN CAMPTONITE DIKES NEAR WHITEHALL, 
WASHINGTON COUNTY, N. Y. 
By J. F. Kk.mi- and V. F. Mahstkrs!. 
Our attention has recently been directed to the occurrence 
of dikes of eruptive rock near the state line between New York 
and Vermont, and nearly due east of Whitehall, N. Y. Mr. 
Ira Sayles, of the United States Geological Survey, came upon 
them while in the field under the direction of Mr. C. D. Wal- 
cott, and the past summer brought them to our notice. The 
field work necessary to the preparation of this paper was done 
by Mr. Marsters, and the rocks were then worked up in the 
laboratory by both the writers. Special interest attaches to 
PRE-CAMB. 
GEOR&IA 
CHAZY,^c,HUDS.R 
1 
DRIFT. 
Err 
these dikes, for the 
reason that no 
mention has been 
made, so far as we 
know, of eruptive 
rocks in this vi- 
cinity, although 
they are known 
some fifty miles or 
more to the north. 
On the accom- 
panying map the 
dikes are repre- 
sented by two 
lines intersecting 
eacii other like a 
capital Y, in the 
Georgia slates 
just southwest of 
the Poultney riv- 
er. The general 
geology of the 
neighborhood, as 
